The U.S. Energy Department said it was backing three offshore wind demonstration projects with up to $47 million to help take advantage of an untapped resource.

Projects slated for the coasts of New Jersey, Oregon and Virginia received financial backing for up to four years to deploy their projects in federal and state waters by 2017.

"The Energy Department is working with public and private partners to harness this untapped resource in a sustainable and economic manner," Energy Secretary Ernest Moniz said in a statement Wednesday.

The Energy Department said the New Jersey project, a combined 25-megawatt facility led by Fisherman's Energy, will feature a type of foundation that is cheaper to build and install than for traditional offshore wind farms.

Principle Power's combined 30-MW facility will use a semi-submersible floating foundation designed specifically for deployment in deep waters off the Oregon coast. The Energy Department said more than 60 percent of the offshore wind resources are found in deep waters.

Two 6-MW wind turbines to be installed 26 miles off the coast of Virginia Beach, led by Dominion Virginia Power, will serve as a demonstration project for wind farms located far from shore in hurricane-prone areas.

There are no commercial offshore wind farms operating in U.S. territorial waters.